For me the lyrics have always been important when listening to music.
In part of my my literature studies I learned the tools to analyse both prose and poetry to find any underlying meanings other than what the printed or spoken words give at a first reading or hearing.
I thought it could be interesting to see how differently we interpret lyrics and find out what they mean for different people.
Not in an academic way, but as a fun and interesting discussion.

I would like to begin with a very haunting song by Kate Bush, based on Emily Brontes' novel 'Wuthering Heights'.

What happens in Kate Bush's adaptation of 'Wuthering Heights'? Is she only retelling the story of Cathy and Heathcliff or can her lyrics be interpreted in another way?

I'm not a particular fan of the novel Wuthering Heights, and I haven't heard Kate Bush do this song. And it's not a good time to watch the video here at work. But reading through the lyrics you post here, it appears to me that Cathy has hit bottom in some way - perhaps dying? - and wants to reconcile with Heathcliff before it's too late. Or maybe it's already too late, and her soul is still yearing for Heathcliff and trying to contact him?

I am a fan of both Kate Bush and the book Wuthering Heights. As for Kate, I don't actually own this particular song. I came to her later, with Hounds of Love. As for the book Wuthering Heights, IMO it's the best work of all three Bronte sisters combined, both for its complex and for-its-day innovative structure, and for its dark powerful theme, what happens to true passion when it is allowed to be twisted into hatred and revenge. It is a very dark book, everyone is an asshole and everyone dies. Sometimes only that kind of book will do. ; ) Catherine "betrays her own heart" in rejecting Heathcliffe and sets in motion her own death, the transformation of Healthcliffe's passion into tortuous cruelty, and the dreadful consequences to her brother, Linton's sister, and ultimately their children. Only the children, in the end, are able to transcend the tragedy. I think in her song Wuthering Heights, Kate has Cathy as a ghost, coming back to "make it right." Some ambiguity here, as it could mean that Cathy regrets her decision in life to marry Linton and be someone she was not and now pines for Heathcliffe from beyond the grave. Or, perhaps she, herself wishes a little ghostly revenge upon Heathcliffe, to haunt him for his misdeeds. But then again, in the novel, Heathcliffe digs up her corpse in order to see her again, so perhaps he welcomes the haunting.

BTW, I liked the video with Kate dressed in white better than the one in red.

I read somewhere that Kate Bush wrote this song quite late during the recordings of her album and that the song just as well could have not been chosen as a track.
The lyrics are based on the novel and follows the plot as Cathy indeed dies and comes back to haunt Heathcliff, as she had promised.
There are on the other hand many different ways to interpret lyrics, which makes literature analysis so much fun, as one interpretation is as right as any other.

When I first read the lyrics I thought that the woman in the song is a mental patient who believes that she is Cathy and stalks someone she calls Heathcliff, which gives the lyrics an even spookier meaning. She says "I'm Cathy I've come home, I'm so cold let me in in your window". She is standing outside and pounds on his window and wants to 'grab his soul away'. Perhaps she has looked too deep into the novel, identifying herself with Cathy and is now out to seek revenge on behalf of her.
Well, that is one way to read those lyrics.

Another song that is open for interpretation is James Taylor's very beautiful 'Never Die Young'.
Taylor seldom reveals what his songs are about and especially who Susan in 'Fire And Rain' is has been debated countless times.
Anyway, what is this song about and more precisely, who are 'they'?